PURPOSE: To obtain a jet water flow having excellent converging properties and to operate a high-speed weaving machine by molding a stabilizer part and an orifice part from a highly hard anti-corrosive material in an integrated way and connecting the bottom of a slit of the stabilizer to a tapered part of the interior of an orifice on a curved surface.

CONSTITUTION: A stabilizer part 1 and an orifice part 2 are molded in an integrated way from a highly hard anti-corrosive zirconia material and a slit 3 is isotropically introduced to the end face of the stabilizer part 1 to make the tip of the inner diameter part of a blade 4 in a given thickness. Further a slit bottom 5 at the rear of the blade 4 is connected to the inside taper of the orifice part 2 at the intersecting point between by a curved surface R to give a jet water flow not oscillating the blade 4 at high speed and having excellent converging properties.